Zhengwen Xiao

Active Negative Pressure Peritoneal Therapy After Abbreviated Laparotomy The Intraperitoneal Vacuum Randomized Controlled Trial

Supplemental Digital Content is Available in the Text. This randomized trial observed a survival difference between patients randomized to the ABThera versus Barkers vacuum pack after abbreviated laparotomy. As this difference did not seem to be mediated by improved peritoneal fluid drainage, fascial closure rates, or markers of systemic inflammation, it should be confirmed by a multicenter trial.

Occult pneumothoraces in critical care: a prospective multicenter randomized controlled trial of pleural drainage for mechanically ventilated trauma patients with occult pneumothoraces.

BACKGROUND Patients with an occult pneumothoraces (OPTXs) may be at risk of tension pneumothoraces (TPTXs) without drainage or pleural drainage complications if treated. METHODS Adults with traumatic OPTXs and requiring positive-pressure ventilation (PPV) were randomized to pleural drainage or observation (one side only enrolled if bilateral). All subsequent care and method of pleural drainage was per attending physician discretion. The primary outcome was a composite of respiratory distress (RD) (need for urgent pleural drainage, acute/sustained increases in O2 requirements, ventilator dysynchrony, and/or charted respiratory events). RESULTS Ninety severely injured patients (mean [SD], Injury Severity Score [ISS], 33 [11]) were studied at four centers: Calgary (55), Toronto (27), Quebec (6), and Sherbrooke (3). Forty were randomized to tube thoracostomy, and 50 were randomized to observation. The risk of RD was similar between the observation and tube thoracostomy groups (relative risk, 0.71; 95% confidence interval, 0.40–1.27). There was no difference in mortality or intensive care unit (ICU), ventilator, or hospital days between groups. In those observed, 20% required subsequent pleural drainage (40% PTX progression, 60% pleural fluid, and 20% other). One observed patient (2%) undergoing PPV at enrollment had a TPTX, which was treated with urgent tube thoracostomy without sequelae. Drainage complications occurred in 15% of those randomized to drainage, while suboptimal tube thoracostomy position occurred in an additional 15%. There were three times (24% vs. 8%) more failures and more RDs (p = 0.01) among those observed with OPTXs requiring sustained PPV versus just for an operation, which increases threefold after a week in the ICU (p = 0.07). CONCLUSION Our results suggest that OPTXs may be safely observed in hemodynamically stable patients undergoing PPV just for an operation, although one third of those requiring a week or more of ICU care received drainage, and TPTXs still occur. Complications of pleural drainage remain unacceptably high, and future work should attempt to delineate specific factors among those observed that warrant prophylactic drainage. LEVEL OF EVIDENCE Therapeutic study, level III.

Potential Use of Remote Telesonography as a Transformational Technology in Underresourced and/or Remote Settings

Mortality and morbidity from traumatic injury are twofold higher in rural compared to urban areas. Furthermore, the greater the distance a patient resides from an organized trauma system, the greater the likelihood of an adverse outcome. Delay in timely diagnosis and treatment contributes to this penalty, regardless of whether the inherent barriers are geographic, cultural, or socioeconomic. Since ultrasound is noninvasive, cost-effective, and portable, it is becoming increasingly useful for remote/underresourced (R/UR) settings to avoid lengthy patient travel to relatively inaccessible medical centers. Ultrasonography is a user-dependent, technical skill, and many, if not most, front-line care providers will not have this advanced training. This is particularly true if care is being provided by out-of-hospital, “nontraditional” providers. The human exploration of space has forced the utilization of information technology (IT) to allow remote experts to guide distant untrained care providers in point-of-care ultrasound to diagnose and manage both acute and chronic illness or injuries. This paradigm potentially brings advanced diagnostic imaging to any medical interaction in a setting with internet connectivity. This paper summarizes the current literature surrounding the development of teleultrasound as a transformational technology and its application to underresourced settings.

Inflammatory mediators in intra-abdominal sepsis or injury - a scoping review.

IntroductionInflammatory and protein mediators (cytokine, chemokine, acute phase proteins) play an important, but still not completely understood, role in the morbidity and mortality of intra-abdominal sepsis/injury. We therefore systematically reviewed preclinical and clinical studies of mediators in intra-abdominal sepsis/injury in order to evaluate their ability to: (1) function as diagnostic/prognostic biomarkers; (2) serve as therapeutic targets; and (3) illuminate the pathogenesis mechanisms of sepsis or injury-related organ dysfunction.MethodsWe searched MEDLINE, PubMed, EMBASE and the Cochrane Library. Two investigators independently reviewed all identified abstracts and selected articles for full-text review. We included original studies assessing mediators in intra-abdominal sepsis/injury.ResultsAmong 2437 citations, we selected 182 studies in the scoping review, including 79 preclinical and 103 clinical studies. Serum procalcitonin and C-reactive protein appear to be useful to rule out infection or monitor therapy; however, the diagnostic and prognostic value of mediators for complications/outcomes of sepsis or injury remains to be established. Peritoneal mediator levels are substantially higher than systemic levels after intra-abdominal infection/trauma. Common limitations of current studies included small sample sizes and lack of uniformity in study design and outcome measures. To date, targeted therapies against mediators remain experimental.ConclusionsWhereas preclinical data suggests mediators play a critical role in intra-abdominal sepsis or injury, there is no consensus on the clinical use of mediators in diagnosing or managing intra-abdominal sepsis or injury. Measurement of peritoneal mediators should be further investigated as a more sensitive determinant of intra-abdominal inflammatory response. High-quality clinical trials are needed to better understand the role of inflammatory mediators.

Efficacy and safety of active negative pressure peritoneal therapy for reducing the systemic inflammatory response after damage control laparotomy (the Intra-peritoneal Vacuum Trial): study protocol for a randomized controlled trial

BackgroundDamage control laparotomy, or abbreviated initial laparotomy followed by temporary abdominal closure (TAC), intensive care unit resuscitation, and planned re-laparotomy, is frequently used to manage intra-abdominal bleeding and contamination among critically ill or injured adults. Animal data suggest that TAC techniques that employ negative pressure to the peritoneal cavity may reduce the systemic inflammatory response and associated organ injury. The primary objective of this study is to determine if use of a TAC dressing that affords active negative pressure peritoneal therapy, the ABThera Open Abdomen Negative Pressure Therapy System, reduces the extent of the systemic inflammatory response after damage control laparotomy for intra-abdominal sepsis or injury as compared to a commonly used TAC method that provides potentially less efficient peritoneal negative pressure, the Barker’s vacuum pack.Methods/DesignThe Intra-peritoneal Vacuum Trial will be a single-center, randomized controlled trial. Adults will be intraoperatively allocated to TAC with either the ABThera or Barker’s vacuum pack after the decision has been made by the attending surgeon to perform a damage control laparotomy. The study will use variable block size randomization. On study days 1, 2, 3, 7, and 28, blood will be collected. Whenever possible, peritoneal fluid will also be collected at these time points from the patient’s abdomen or TAC device. Luminex technology will be used to quantify the concentrations of 65 mediators relevant to the inflammatory response in peritoneal fluid and plasma. The primary endpoint is the difference in the plasma concentration of the pro-inflammatory cytokine IL-6 at 24 and 48 h after TAC dressing application. Secondary endpoints include the differential effects of these dressings on the systemic concentration of other pro-inflammatory cytokines, collective peritoneal and systemic inflammatory mediator profiles, postoperative fluid balance, intra-abdominal pressure, and several patient-important outcomes, including organ dysfunction measures and mortality.DiscussionResults from this study will improve understanding of the effect of active negative pressure peritoneal therapy after damage control laparotomy on the inflammatory response. It will also gather necessary pilot information needed to inform design of a multicenter trial comparing clinical outcomes among patients randomized to TAC with the ABThera versus Barker’s vacuum pack.Trial registrationClinicalTrials.gov identifierhttp://www.clicaltrials.gov/ct2/show/NCT01355094

The feasibility of nurse practitioner-performed, telementored lung telesonography with remote physician guidance - ‘a remote virtual mentor’

BackgroundPoint-of-care ultrasound (POC-US) use is increasingly common as equipment costs decrease and availability increases. Despite the utility of POC-US in trained hands, there are many situations wherein patients could benefit from the added safety of POC-US guidance, yet trained users are unavailable. We therefore hypothesized that currently available and economic ‘off-the-shelf’ technologies could facilitate remote mentoring of a nurse practitioner (NP) to assess for recurrent pneumothoraces (PTXs) after chest tube removal.MethodsThe simple remote telementored ultrasound system consisted of a handheld ultrasound machine, head-mounted video camera, microphone, and software on a laptop computer. The video output of the handheld ultrasound machine and a macroscopic view of the NPs hands were displayed to a remote trauma surgeon mentor. The mentor instructed the NP on probe position and US machine settings and provided real-time guidance and image interpretation via encrypted video conferencing software using an Internet service provider. Thirteen pleural exams after chest tube removal were conducted.ResultsThirteen patients (26 lung fields) were examined. The remote exam was possible in all cases with good connectivity including one trans-Atlantic interpretation. Compared to the subsequent upright chest radiograph, there were 4 true-positive remotely diagnosed PTXs, 2 false-negative diagnoses, and 20 true-negative diagnoses for 66% sensitivity, 100% specificity, and 92% accuracy for remotely guided chest examination.ConclusionsRemotely guiding a NP to perform thoracic ultrasound examinations after tube thoracostomy removal can be simply and effectively performed over encrypted commercial software using low-cost hardware. As informatics constantly improves, mentored remote examinations may further empower clinical care providers in austere settings.

Enabling the Mission Through Trans-Atlantic Remote Mentored Musculoskeletal Ultrasound: Case Report of a Portable Hand-Carried Tele-ultrasound System for Medical Relief Missions

Modern medical practice has become extremely dependent upon diagnostic imaging technologies to confirm the results of clinical examination and to guide the response to therapies. Of the various diagnostic imaging techniques, ultrasound is the most portable modality and one that is repeatable, dynamic, relatively cheap, and safe as long as the imaging provided is accurately interpreted. It is, however, the most user-dependent, a characteristic that has prompted the development of remote guidance techniques, wherein remote experts guide distant users through the use of information technologies. Medical mission work often brings specialist physicians to less developed locations, where they wish to provide the highest levels of care but are often bereft of diagnostic imaging resources on which they depend. Furthermore, if these personnel become ill or injured, their own care received may not be to the standard they have left at home. We herein report the utilization of a compact hand-carried remote tele-ultrasound system that allowed real-time diagnosis and follow-up of an acutely torn adductor muscle by a team of ultrasonographers, surgeons, and physicians. The patient was one of the mission surgeons who was guided to self-image. The virtual network of supporting experts was located across North America, whereas the patient was in Lome, Togo, West Africa. The system consisted of a hand-carried ultrasound, the output of which was digitized and streamed to the experts within standard voice-over-Internet-protocol software with an embedded simultaneous videocamera image of the ultrasonographers hands using a customized graphical user interface. The practical concept of a virtual tele-ultrasound support network was illustrated through the clinical guidance of multiple physicians, including National Aeronautics and Space Administration Medical Operations remote guiders, Olympic team-associated surgeons, and ultrasound-focused emergentologists.

High Mobility Group Box-1 Protein and Outcomes in Critically Ill Surgical Patients Requiring Open Abdominal Management

Background. Previous studies assessing various cytokines in the critically ill/injured have been uninformative in terms of translating to clinical care management. Animal abdominal sepsis work suggests that enhanced intraperitoneal (IP) clearance of Damage-Associated Molecular Patterns (DAMPs) improves outcome. Thus measuring the responses of DAMPs offers alternate potential insights and a representative DAMP, High Mobility Group Box-1 protein (HMGB-1), was considered. While IP biomediators are being recognized in critical illness/trauma, HMGB-1 behaviour has not been examined in open abdomen (OA) management. Methods. A modified protocol for HMGB-1 detection was used to examine plasma/IP fluid samples from 44 critically ill/injured OA patients enrolled in a randomized controlled trial comparing two negative pressure peritoneal therapies (NPPT): Active NPPT (ANPPT) and Barkers Vacuum Pack NPPT (BVP). Samples were collected and analyzed at the time of laparotomy and at 24 and 48 hours after. Results. There were no statistically significant differences in survivor versus nonsurvivor HMGB-1 plasma or IP concentrations at baseline, 24 hours, or 48 hours. However, plasma HMGB-1 levels tended to increase continuously in the BVP cohort. Conclusions. HMGB-1 appeared to behave differently between NPPT cohorts. Further studies are needed to elucidate the relationship of HMGB-1 and outcomes in septic/injured patients.